The keys to the Phillies’ series at Coors Field would have been much different had they made it out to Colorado earlier in the week. But Rockies star shortstop Troy Tulowitzki is injured again and will miss 4-6 weeks. Carlos Gonzalez and Dexter Fowler are also day-to-day.

The Phils have performed very well lately at the hitters' haven in Denver. They’re 12-3 in their last 15 games at Coors.

Here are some keys to the Phillies’ series with the 35-32 Rockies:

Starters must last six innings

Do you trust this Phillies bullpen to get more than nine outs anywhere, let alone Coors Field?

Six innings are the minimum the Phillies need from Kyle Kendrick, Jon Pettibone and Cole Hamels this weekend. It shouldn’t be a major issue –- the Phillies do lead the majors with 46 quality starts and their starting pitchers rank third in innings, behind only the Cardinals and Reds.

Up-and-in, low-and-away to CarGo

Gonzalez destroys pitches in the middle of the plate, but his favorite pitch is the low-and-inside fastball. He’s a prototypical lefty power hitter in that regard.

He does, however, struggle on pitches low and away. Part of it is because he stands so far from the plate and has an awkward-yet-effective closed batting stance.

Gonzalez is hitting better than .450 on pitches middle-in and low-and-in. But he doesn’t have a single hit this season on pitches up-and-in, according to ESPN Hot Zones.

Hitting spots is key against Gonzalez, because while he’s hitting only .250 on pitches low and away, he’s hitting .407 when they’re away but slightly elevated.

With Tulowitzki out, it’s easier to pitch around Gonzalez. But Michael Cuddyer is having a heck of a season batting fifth (.337 BA, .995 OPS) and Tulo’s replacement Josh Rutledge hit over .350 in his first 23 games replacing him last season. It’s still a potent offense without Tulowitzki on the field.

Revere must stay hot

Ben Revere has seven hits in his last two games and is now up to a season-high .266. He’s hit .316 with a .360 OBP since May 1.

Since their one-run loss to the Royals in their fifth game of the year, the Phillies are 10-5 when Revere has a multi-hit game.